1. Field of the Invention
The present invention relates to an ion beam processing system and sample processing method.
2. Description of Related Art
Methods for mechanically polishing samples are known as sample preparation methods for observations and analyses using electron microscopy. In a mechanical polishing method, however, a force acts on the worked surface. Therefore, softer parts may be deleted earlier, forming unevenness, or the softer parts may be crushed. Furthermore, a harder material may be buried in softer parts. Consequently, with a method of mechanical polishing, it has been difficult to smoothly polish junctions or boundaries of materials of different hardnesses. In this way, with a mechanical polishing method, it has been difficult to prepare a sample cross section without varying the morphology or composition of the sample.
In view of this problem, JP-A-2011-192521, for example, discloses an ion beam processing system for processing samples by a cross section polisher (CP) that prepares a cross section in a manner relatively unaffected by the processing work. In the ion beam processing system disclosed in JP-A-2011-192521, a shield plate for blocking the ion beam is mounted over the sample to control the irradiated region. The beam is directed at the region of the sample not shielded by the shield plate to process the sample.
In recent years, electric vehicles have attracted attention due to environmental issues, energy problems, and so on. Developments of lithium-ion batteries for such electric vehicles have been accelerated. In the course of development of lithium-ion batteries, the structure is observed and an elemental analysis is made. Because lithium is a material readily reacting with oxygen and nitrogen, it is necessary to perform all processing steps including sample preparation, observation, and analysis under an environment isolated from the atmosphere.
The ion beam processing system disclosed in JP-A-2011-192521 has the problem that the sample is exposed to the atmosphere either when the sample is loaded into the processing system or until the processed sample is transferred and introduced into an instrument such as an electron microscope for observation or analysis of the sample. As a result, the sample such as lithium will change in quality.